Early stages of protein crystallization as revealed by emerging optical waveguide technology

Synopsis: Dual polarization interferometry supports recent hypotheses that the critical nuclei of protein crystals arise from a large stable disordered protein aggregate. It also promises early detection for the onset of protein crystallization in crystallization trials.

Modelling the X-ray powder diffraction of nitrogen-expanded austenite using the Debye formula

Synopsis: Simulations using the Debye formula have been performed to explain the X-ray powder diffraction patterns of stress-free and homogeneous samples of nitrogen-expanded austenite, synthesized by low-temperature gaseous nitriding of stainless steel.

Time-resolved diffraction studies into the pressure acid leaching of nickel laterite ores: a comparison of laboratory and synchrotron X-ray experiments

Synopsis: Time-resolved diffraction studies into the pressure acid leaching of nickel laterite ores have been conducted using laboratory X-ray and synchrotron radiation sources. The results are compared with respect to reaction mechanism and data analysis techniques.

A Yb3+-doped NaY(WO4)2 crystal grown by the Czochralski technique

Synopsis: A series of possible growth faces (hkl) were determined from the crystal lattice and symmetry of Yb3+-doped NaY(WO4)2 according to the Bravais-Friedel Donnay-Harker theory, and the relationship among crystal structure, growth habits and crystal morphology is discussed. In addition, the thermal properties of the crystal, including the specific heat, thermal expansion, thermal diffusion and thermal conductivity, are investigated.

Different models for the polar nanodomain structure of PZN and other relaxor ferroelectrics

Synopsis: Computer simulations have been carried out to test the recently proposed model for the nanodomain structure of relaxor ferroelectrics such as lead zinc niobate (PZN). The present results confirm that and as well as the previously proposed types of Pb displacement are viable possibilities, but the number of domain boundaries required to produce sufficiently strong diffuse rods of scattering means that individual domains cannot be described as three-dimensional and must still be considered to be relatively thin plates.

Size-broadening anisotropy in whole powder pattern fitting. Application to zinc oxide and interpretation of the apparent crystallites in terms of physical models

Synopsis: A new anisotropic size-broadening model, based on a spherical-harmonics representation and convenient for implementation into Rietveld programs, is described. The model is interpreted in terms of physical models by using ellipsoidal and cylindrical crystallites with lognormal size distributions.

Application of small-angle scattering to study the effects of moisture content on a native soy protein

Synopsis: The effect of moisture content on native soy glycinin is determined using small-angle scattering techniques. Scattering data suggest that the protein expands as the moisture content increases and a hexagonal crystal structure is demonstrated. Scattering data are complemented by electron microscopy, indicating a corresponding expansion of the microstructure with moisture content.

Structure of K2TaF7 at 993 K: the combined use of synchrotron powder data and solid-state DFT calculations

Synopsis: The structure of the title compound was optimized by energy minimization in the solid state at the DFT level of theory using the lattice parameters obtained from high-temperature synchrotron X-ray powder diffraction data.

Synopsis: The pressure dependences of the lattice parameters of two spin transition compounds, Fe(PM-AzA)2(NCS)2 and Fe(PM-BiA)2(NCS)2 [PM is N-2'-pyridylmethylene, AzA is 4-(phenylazo)aniline and BiA is 4-aminobiphenyl], have been derived from neutron powder diffraction measurements at ambient temperature.

VESTA: a three-dimensional visualization system for electronic and structural analysis

Synopsis: A cross-platform program, VESTA, has been developed for three-dimensional visualization of both structural models and volumetric data such as electron and nuclear densities, Patterson functions, and wavefunctions.